This invention relates generally to improvements in covers for electrical energy meters, such as watthour meters. The invention particularly concerns a composite cover and an improved mating ring.
Watthour meter covers function to protect the meter's measuring element from the weathering environment, to prevent tampering and to provide a safety barrier for the voltage potential across the meter. The electrical energy metering industry normally utilizes a circular metallic mating ring to facilitate the attachment of the dome shaped plastic or glass meter cover to the meter base. The metallic mating ring and clips are typically made of stainless steel or aluminum and are spot-welded together. Metal mating rings are assembled from several parts which require roll forming, punching and spot welding to complete the manufacture of the ring. The clips are normally spot welded onto the ring when engaged to the meter cover flange. Due to the fabrication process, the metal ring is costly and requires significant tooling and assembly fixtures to assure consistent results.
The fabricated metal mating ring also limits the flexibility of controlling the relative location of optical ports and reset hardware features on the meter covers. The stainless steel mating ring has other disadvantages due to the fact that its sharp edges often result in minor cuts to personnel during the forming and assembly operations.